Use external hip and hipcub headers when HOOMD_GPU_PLATFORM=CUDA

[joaander]

Description

• Remove the vendored hip and hipcub headers. Instead, use find_package(hip) to find external headers.
• Change compiler definitions to support modern versions of hip.

Motivation and context

CUDA 13 contains many breaking changes and the vendored headers do not support it.
By using external hip libraries, HOOMD-blue will gain support for new versions of CUDA as soon as upstream adds support (at this time the latest release of hipcub does not support CUDA 13).

conda-forge does not support HIP_PLATFORM=nvidia (conda-forge/hip-feedstock#9) in hip-devel and lacks a hipcub package entirely. Therefore, users that build HOOMD from source for NVIDIA GPUs will need to install hip and hipcub headers:

• https://rocmdocs.amd.com/projects/HIP/en/latest/install/build.html
• https://rocm.docs.amd.com/projects/hipCUB/en/latest/install/hipCUB-install-with-cmake.html

How has this been tested?

HOOMD-blue compiles and passes tests with CUDA 12.9, rocm-systems:hip-version_7.2.53220, and rocm-libraries:rocm-7.1.0 locally. CI checks have been updated accordingly. Patches to hip and hipcub fix build errors with CUDA 12.5–12.8.

Checklist:

• I have reviewed the Contributor Guidelines.
• I agree with the terms of the HOOMD-blue Contributor Agreement.
• My name is on the list of contributors (sphinx-doc/credits.rst) in the pull request source branch.
• I have summarized these changes in CHANGELOG.rst following the established format.

[joaander]

@mphoward, what do you think of using an external HIP library even when HOOMD_GPU_PLATFORM=CUDA?

Ideally we could avoid this by using hipper everywhere, but that would be a lot more work.

In any case, I won't merge this until hipcub supports CUDA 13. Until then, these changes introduce additional complexity for developers with no benefit.

[mphoward]

Hmm, it isn't ideal to require CUDA users to download and compile HIP, but I agree this fix is substantially less work than getting hipper updated to modern rocm and implemented everywhere in HOOMD. (This work is still on my todo list for a long time, but I've been unable to get to it.)

Do you have a rough sense of when hipcub will support for CUDA 13 and this will be ready to merge? We could always temporarily require HIP, then relax this requirement later if we did complete the extra work.